Progress in the ecology and conservation of giant pandas

Giant panda (Ailuropoda melanoleuca) conservation is a possible success story in the making. If extinction of this iconic endangered species can be avoided, the species will become a showcase program for the Chinese government and its collaborators. We reviewed the major advancements in ecological science for the giant panda, examining how these advancements have contributed to panda conservation. Pandas’ morphological and behavioral adaptations to a diet of bamboo, which bear strong influence on movement ecology, have been well studied, providing knowledge to guide management actions ranging from reserve design to climate change mitigation. Foraging ecology has also provided essential information used in the creation of landscape models of panda habitat. Because habitat loss and fragmentation are major drivers of the panda population decline, efforts have been made to help identify core habitat areas, establish where habitat corridors are needed, and prioritize areas for protection and restoration. Thus, habitat models have provided guidance for the Chinese governments’ creation of 67 protected areas. Behavioral research has revealed a complex and efficient communication system and documented the need for protection of habitat that serves as a communication platform for bringing the sexes together for mating. Further research shows that den sites in old‐growth forests may be a limiting resource, indicating potential value in providing alternative den sites for rearing offspring. Advancements in molecular ecology have been revolutionary and have been applied to population census, determining population structure and genetic diversity, evaluating connectivity following habitat fragmentation, and understanding dispersal patterns. These advancements form a foundation for increasing the application of adaptive management approaches to move panda conservation forward more rapidly. Although the Chinese government has made great progress in setting aside protected areas, future emphasis will be improved management of pandas and their habitat.     

岩豆凝集素的纯化及其分子残基的化学修饰和活性关系

岩豆种子经侵取、硫酸铵分级、ＤＥＡＥ－纤维素离子交换和ＳｅｐｈａｄｅｘＧ－１００分子筛层析，获得ＦＰＬＣ上单一的凝集素样品，对此纯化的凝集素样品用Ｎ－溴代丁二酰亚胺、Ｎ－乙基顺丁烯二酰亚胺、二流苏糖醇，碘乙酸和对氯汞苯甲酸修饰其分子内的色氨酸和巯基．经计算，该凝集素分子内含有４个色氨酸和２４个流基，当色氨酸被修饰后其凝集活性全部丧失，而巯基被修饰后对其凝血活性无任何影响，表明巯基与凝集素分子的凝血活性无关，而色氨酸则是凝集活性所必需的基团．     

人工接种堆肥和自然堆肥微生物区系与分子多态性的变化

采用传统培养方法和PCR-DGGE技术研究了人工接种堆肥和自然堆肥微生物群落的演变过程。结果表明:(1)传统培养方法显示,两种堆肥堆制过程中微生物数量均呈“升高—降低—升高—降低”变化趋势,整个堆肥过程中细菌数量占优势。(2)DGGE图谱显示,两种堆肥不同时期存在不同的细菌种群,其条带数量亦呈“升高—降低—升高—降低”变化趋势。堆肥升温期条带丰富但优势条带不明显;堆肥高温期条带数量减少但出现优势条带,表明高温阶段以嗜热菌或耐高温菌为主;堆肥降温期条带数量再次增多;堆肥腐熟期条带数量少且无优势条带,表明腐熟阶段微生物种群数量少且代谢强度趋于平缓。(3)DGGE图谱表明,人工接种菌株成为堆肥高温期优势菌株。人工接种增加了堆肥中微生物总量,提高了堆肥微生物种群多样性,并且促进了堆肥菌群演替,从而缩短堆肥腐熟时间。     

拓扑指数在定量结构生物降解性关系中的应用

本文采用二氧化碳生成量实验，对训练组有机物，利用逐步回归分析程序，从计算和十四种分子连接性指数中筛选出与生物降解性最为相关的分子结构描述参数，建立定量结构－生物降解性关系模型，其相关系数为０．９３１，利用该模型对预测组质的预测结果表明，此模型对芳香化合物的好氧生物降解性具有良好的预测能力，其正确预测率达８３．３％。     

Managing Individuals' Contributions to Maximize the Allelic Diversity Maintained in Small, Conserved Populations

Abstract:  The maintenance of diversity is, from a genetic perspective, one of the key aims in a conservation program. Because the most widely used measure of genetic diversity is the expected heterozygosity of the population, or gene diversity (GD), most research has been devoted to finding optimal strategies for maximizing this parameter. Little attention has been paid, however, to the development of strategies to manage allelic diversity (AD), the number of alleles maintained in the population. Using computer simulations, we show that the strategies that maximize GD, by managing contributions from parents, keep levels of AD as high as strategies maximizing AD itself, for a wide range of situations including different numbers of molecular markers used and the possibility of evaluating a number of offspring per parent to make decisions. Because maximization of GD also minimizes levels of inbreeding, this should be the strategy of choice in any conservationprogram.     

识别黄山药、穿龙薯蓣和盾叶薯蓣的分子标记建立

在对黄山药、穿龙薯蓣和盾叶薯蓣的psbA-trnH片段序列分析的基础上,根据3种薯蓣在该片段上的特征序列位点设计了用于识别3种薯蓣的寡核苷酸片段,并作为PCR反应的引物,将3种薯蓣的特征标记引物与psbAf-trn-Hr配合使用建立了识别3种薯蓣的显性和共显性两种检测方式,辅以NaOH碱法快速提取薯蓣干燥根茎总DNA,为3种薯蓣相互间快速、准确的鉴别创造了条件.图3表2参9     

大气中痕量挥发性有机物的结构表征和保留时间的估计与预测

采用分子电性距离矢量（MEDV）表征大气中痕量挥发性有机物的分子结构,同时采用逐步回归结合统计检测对模型进行变量筛选,建立了大气中痕量挥发性有机物定量结构-色谱保留（QSRR）关系的8个变量和5个变量模型,两种QSRR模型的建模计算值复相关系数（R）分别为0.937和0.931;留一法（leave-one-out）交互校验复相关系数（RCV）分别为0.901和0.906,表明模型具有良好的估计能力与稳定性.     

Concentration Evolution of Gas Species within a Collapsing Bubble in a Liquid Medium

In this study numerical methods are used to investigate the relationship between chemical concentration of gas species within a cavitating bubble, equilibrium radius of the gas bubble and pressure variations in the ambient liquid. For this purpose, governing equations are developed to describe the dynamic equilibrium of a bubble in a flowing fluid and mass transfer between gas and liquid phases, where it was assumed that gases undergo isothermal compression, obey the ideal gas law, Henry law. It is further assumed that the concentration of each phase within the bubble is uniform. The resulting nonlinear equations are solved using implicit Trapezoidal method with Newton iteration. Four gas species are modeled under various initial and ambient pressure variation conditions. These conditions maybe considered to represent typical cavitation events. The numerical results obtained are presented in terms of dimensionless numbers. These results indicate that chemical damage maybe an important component of cavitation surface damage, since high concentration profiles may develop within a collapsing bubble. Proposed formulation and numerical solutions are simple and cost effective to implement. The results presented in this study maybe used to benchmark experimental investigations or other more complex solutions, which are outside the scope of this study.     

Modelling the environmental degradation of water contaminants. Kinetics and mechanism of the riboflavin-sensitised-photooxidation of phenolic compounds

The aerobic visible-light-photosensitised irradiation of methanolic solutions of either of the phenolic-type contaminants model compounds (ArOH) p-phenylphenol (PP), p-nitrophenol (NP) and phenol (Ph), and for two additional phenolic derivatives, namely p-chlorophenol (ClP) and p-methoxyphenol (MeOP), used in some experiments, was carried out. Employing the natural pigment riboflavin (Rf) as a sensitiser, the degradation of both the ArOH and the very sensitiser was observed. A complex mechanism, common for all the ArOH studied, operates. It involves superoxide radical anion (O₂^√−) and singlet molecular oxygen (O₂(¹Δ_g)) reactions. Maintaining Rf in sensitising concentrations levels (≈0.02 mM), the mechanism is highly dependent on the concentration of the ArOH. Kinetic experiments of oxygen and substrate consumption, static fluorescence, laser flash photolysis and time-resolved phosophorescence detection of O₂(¹Δ_g) demonstrate that at ArOH concentrations in the order of 10 mM, no chemical transformation occurs due to the complete quenching of Rf singlet excited state. When ArOH is present in concentrations in the order of mM or lower, O₂^√− is generated from the corresponding Rf radical anion, which is produced by electron transfer reaction from the ArOH to triplet excited Rf. The determined reaction rate constants for this step show a fairly good correlation with the electron-donor capabilities for Ph, PP, NP, ClP and MeOP. In this context, the main oxidative species is O₂^√−, since O₂(¹Δ_g) is quenched in an exclusive physical fashion by the ArOH. The production of O₂^√− regenerates Rf impeding the total degradation of the sensitiser. This kinetic scheme could partially model the fate of ArOH in aquatic media containing natural photosensitisers, under environmental conditions.     

分子生物技术在环境工程微生物领域中的应用

目前分子生物技术发展日新月异,已渗透到各相关学科。本文综述了分子生物技术的基本原理与方法,及其在环境工程微生物领域的应用。讨论了分子生物技术在环境工程微生物的检测应用及在污泥、生物膜、底泥和土壤等微生物种群的多样性分析方面,以及环境工程菌的挑选和培养等方面的研究成果及其巨大研究前景,对该技术在环境工程领域的应用与发展提出了一些见解。